A study of Schottky barrier height inhomogeneity on In/p-Silicon

The current-voltage characteristics of In/p-Si Schottky diode measured over a temperature range of 120-360 K have been interpreted on the basis of thermionic emission across an inhomogenous Schottky contact. The experiment shows that the apparent barrier height be increases and ideality factor decreases from 0.26 eV and 6.36 at 120 K to 0.70 eV and 1.91 at 360 K respectively. The variation of effective Schottky barrier height and ideality factor with temperature has been explained considering lateral inhomogeneties at the metal-semiconductor interface. We have also discussed whether or not the junction current has been connected themionic field emission (TFE) mechanisms. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2203

Schottky contact of gallium on p-type silicon

The evolution of barrier at Schottky contact and its stabilization to value characterized by the barrier height and unambiguous measurement is still being curiously perused as they hold the key control and manufacture of tailor made Schottky devices for a host of existing and potential for future applications in electronics, optoelectronics and microwave devices. In this context, gallium – silicon Schottky diode has been fabricated and analyzed. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2203

Analysis of the Inhomogeneous Barrier in In/p-Si Schottky Contact and Modified Richardson Plot

The current-voltage (I-V) characteristics of In/p-Si Schottky barrier contact were measured over the temperature range 230-360 K with interval of 10 K. The calculated zero bias barrier height () and the ideality factor (n) using thermionic theory show strong temperature dependence. The experimental values of and n for In/p-Si Schottky contact range from 0.70 eV and 1.91 (at 360 K) to 0.49 eV and 2.99 (at 230 K) respectively. The conventional Richardson plot exhibits nonlinearity at lower temperature. The Richardson constant determined from intercept at the ordinate of this experimental linear portion is the value of 2.07 × 10 – 8 A/cm2K2 which is much lower than the theoretical value 32 A/cm2K2 for holes in p-type silicon. The temperature dependence of Schottky barrier characteristics of the contact was interpreted on the basis of the existence of Gaussian distribution of the barrier height around a mean value due to barrier height inhomogeneties prevailing at the metal semiconductor interface. The modified plot gives = 1.17 eV and A* = 31.16 A/cm2K2 with standard deviation = 0.16 V

Phase Transition Sensitive Schottky Barriers In Ga-Si(P) Contacts

Investigation and understanding of Schottky diodes continue to be interesting both for basic as well as technological points of view. Even now the evolutionary aspects of such contacts are not very clearly understood. In this paper it is shown that in respect of interfacial strain contribution to the barrier heights of such contacts semiconductor – liquid metal contacts are relatively better placed than solid semiconductor-solid metal contacts. Results on Ga-Si(p) contact are discussed in this paper to show phase sensitive contribution to the barrier height of such Schottky contacts. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3099

A Study of Schottky Barrier Height Inhomogeneity on In/P-Silicon

The current-voltage characteristics of In/p-Si Schottky diode measured over a temperature range of 120-360 K have been interpreted on the basis of thermionic emission across an inhomogenous Schottky contact. The experiment shows that the apparent barrier height Φbe increases and ideality factor decreases from 0.26 eV and 6.36 at 120 K to 0.70 eV and 1.91 at 360 K respectively. The variation of effective Schottky barrier height and ideality factor with temperature has been explained considering lateral inhomogeneties at the metal-semiconductor interface. We have also discussed whether or not the junction current has been connected themionic field emission (TFE) mechanisms

Quantum discord evolution of three-qubit states under noisy channels

We investigated the dissipative dynamics of quantum discord for correlated qubits under Markovian environments. The basic idea in the present scheme is that quantum discord is more general, and possibly more robust and fundamental, than entanglement. We provide three initially correlated qubits in pure Greenberger-Horne-Zeilinger (GHZ) or W state and analyse the time evolution of the quantum discord under various dissipative channels such as: Pauli channels $\sigma_{x}$, $\sigma_{y}$, and $\sigma_{z}$, as well as depolarising channels. Surprisingly, we find that under the action of Pauli channel $\sigma_{x}$, the quantum discord of GHZ state is not affected by decoherence. For the remaining dissipative channels, the W state is more robust than the GHZ state against decoherence. Moreover, we compare the dynamics of entanglement with that of the quantum discord under the conditions in which disentanglement occurs and show that quantum discord is more robust than entanglement except for phase flip coupling of the three qubits system to the environment.Comment: 17 pages, 4 figures, accepted for publication in EPJ

Processing of aluminum-graphite particulate metal matrix composites by advanced shear technology

Copyright @ 2009 ASM International. This paper was published in Journal of Materials Engineering and Performance 18(9) and is made available as an electronic reprint with the permission of ASM International. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplications of any material in this paper for a fee or for commercial purposes, or modification of the content of this paper are prohibited.To extend the possibilities of using aluminum/graphite composites as structural materials, a novel process is developed. The conventional methods often produce agglomerated structures exhibiting lower strength and ductility. To overcome the cohesive force of the agglomerates, a melt conditioned high-pressure die casting (MC-HPDC) process innovatively adapts the well-established, high-shear dispersive mixing action of a twin screw mechanism. The distribution of particles and properties of composites are quantitatively evaluated. The adopted rheo process significantly improved the distribution of the reinforcement in the matrix with a strong interfacial bond between the two. A good combination of improved ultimate tensile strength (UTS) and tensile elongation (e) is obtained compared with composites produced by conventional processes.EPSR

Quantum Correlation in One-dimensional Extend Quantum Compass Model

We study the correlations in the one-dimensional extended quantum compass model in a transverse magnetic field. By exactly solving the Hamiltonian, we find that the quantum correlation of the ground state of one-dimensional quantum compass model is vanishing. We show that quantum discord can not only locate the quantum critical points, but also discern the orders of phase transitions. Furthermore, entanglement quantified by concurrence is also compared.Comment: 8 pages, 14 figures, to appear in Eur. Phys. J.

Analysis of the Inhomogeneous Barrier in In/p-Si Schottky Contact and Modified Richardson Plot

The current-voltage (I-V) characteristics of In/p-Si Schottky barrier contact were measured over the temperature range 230-360 K with interval of 10 K. The calculated zero bias barrier height () and the ideality factor (n) using thermionic theory show strong temperature dependence. The experimental values of and n for In/p-Si Schottky contact range from 0.70 eV and 1.91 (at 360 K) to 0.49 eV and 2.99 (at 230 K) respectively. The conventional Richardson plot exhibits nonlinearity at lower temperature. The Richardson constant determined from intercept at the ordinate of this experimental linear portion is the value of 2.07 × 10 – 8 A/cm2K2 which is much lower than the theoretical value 32 A/cm2K2 for holes in p-type silicon. The temperature dependence of Schottky barrier characteristics of the contact was interpreted on the basis of the existence of Gaussian distribution of the barrier height around a mean value due to barrier height inhomogeneties prevailing at the metal semiconductor interface. The modified plot gives = 1.17 eV and A* = 31.16 A/cm2K2 with standard deviation = 0.16 V

Dynamics of multipartite quantum correlations under decoherence

Quantum discord is an optimal resource for the quantification of classical and non-classical correlations as compared to other related measures. Geometric measure of quantum discord is another measure of quantum correlations. Recently, the geometric quantum discord for multipartite states has been introduced by Jianwei Xu [arxiv:quant/ph.1205.0330]. Motivated from the recent study [Ann. Phys. 327 (2012) 851] for the bipartite systems, I have investigated global quantum discord (QD) and geometric quantum discord (GQD) under the influence of external environments for different multipartite states. Werner-GHZ type three-qubit and six-qubit states are considered in inertial and non-inertial settings. The dynamics of QD and GQD is investigated under amplitude damping, phase damping, depolarizing and flipping channels. It is seen that the quantum discord vanishes for p>0.75 in case of three-qubit GHZ states and for p>0.5 for six qubit GHZ states. This implies that multipartite states are more fragile to decoherence for higher values of N. Surprisingly, a rapid sudden death of discord occurs in case of phase flip channel. However, for bit flip channel, no sudden death happens for the six-qubit states. On the other hand, depolarizing channel heavily influences the QD and GQD as compared to the amplitude damping channel. It means that the depolarizing channel has the most destructive influence on the discords for multipartite states. From the perspective of accelerated observers, it is seen that effect of environment on QD and GQD is much stronger than that of the acceleration of non-inertial frames. The degradation of QD and GQD happens due to Unruh effect. Furthermore, QD exhibits more robustness than GQD when the multipartite systems are exposed to environment.Comment: 15 pages, 4 figures, 4 table